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Summary
| Description |
English: Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. The downdraft ventilation shaft is 100' left of the pillar. Arrows show directions of air flow. Access to the face is through roadways through the gob, protected by packwalls, and with the roof "brushed" to maintain clearance as the roof subsides. |
| Date | |
| Source | Coal Mining Methods in Missouri, School of Mines and Metallurgy Bulletin, Vol. 5, No. 4, University of Missouri, Rolla |
| Author | William Walbridge Weigel |
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This image might not be in the public domain outside of the United States; this especially applies in the countries and areas that do not apply the rule of the shorter term for US works, such as Canada, Mainland China (not Hong Kong or Macao), Germany, Mexico, and Switzerland. The creator and year of publication are essential information and must be provided. See Wikipedia:Public domain and Wikipedia:Copyrights for more details.
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| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 15:15, 2 July 2009 | | 738 × 1,000 (133 KB) | Douglas W. Jones | {{Information |Description={{en|1=Original caption: "Fig. 24. -- Plan of individual roadway longwall mine." The three-compartment hoisting shaft is in the center of the central pillar, which is not mined in order to avoid subsidance around the hoist. T |
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